Characteristics and Stability of Incidental Iron Oxide Nanoparticles during Remediation of a Mining-Impacted Stream.
Environ Sci Technol
; 53(19): 11214-11222, 2019 Oct 01.
Article
em En
| MEDLINE
| ID: mdl-31448904
ABSTRACT
Acid mine drainage (AMD) produces nanoparticulate Fe oxides and sorbed toxic metals, such as Cu and Zn. As an indirect product of human activity, these Fe oxides can be classified as incidental nanoparticles (INPs) and their colloidal aggregates. Research in nanoparticle fate and transport has advanced with the development of single particle inductively coupled plasma-mass spectrometry (spICP-MS), but AMD INPs have received little attention. We examined the characteristics and abundance of Fe oxide INPs in an AMD-impacted stream over the first 6 months of remediation. Fe and Cu INP concentrations were approximately 107 and 105 particles mL-1, before and after treatment, respectively. Overall, â¼4 Cu-containing INPs were counted for every 100 Fe-containing INPs. We also studied surface chemistry changes during the treatment period using hematite, a model Fe INP, suspended in filtered field waters. Changes in zeta potential and INP size, measured by dynamic light scattering, support that the contaminated stream chemistry (low pH, high ionic strength) promoted rapid aggregation while improved water quality favored stability. However, the water chemistry and INP stability during snowmelt were additionally impacted by electrolyte dilution, the addition of dissolved organic matter, and physical scouring. By linking field measurements to laboratory experiments, this work explores the effects of surface chemistry on AMD-generated INP behavior before and during remediation in a hydrologically dynamic alpine stream. To our knowledge, this is the first investigation of remediation effects on AMD INPs and the first use of spICP-MS as a technique to measure them.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Poluentes Químicos da Água
/
Nanopartículas
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article